The present invention is directed to an electromagnetic flow control valve assembly and more particularly to an electromagnetic flow control valve assembly which controls a fluid flow between inlet and outlet ports in proportion to the applied electric current flow.
Prior art valve assemblies are known having a valve member to control fluid communication between inlet and outlet ports in response to applied electric current flow. However, in situations where different fluid pressures prevail at the inlet and outlet ports, such as a vacuum pressure at the outlet port and an atmospheric pressure at the inlet port, the vacuum pressure at the outlet port will urge the valve member, which is in its closed position, in one direction due to the difference in pressures at the inlet and outlet ports. Therefore, a problem has been encountered wherein the valve member cannot be moved exactly in proportion to the applied electric current flow especially when there are frequent changes in the vacuum pressure. As a result, the output fluid flow may not be controlled exactly in proportion to the applied electric current flow.